usb: typec: intel_pmc_mux: Add support for USB4

The PMC mux-agent can be used also to enter USB4 mode. The
mux-agent does not have USB4 specific message, but it can be
put into the TBT3 alternate mode also with USB4. That is OK
because the controller is in any case the same with TBT3 and
USB4.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20200701115618.22482-5-heikki.krogerus@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/mux/intel_pmc_mux.c

@@ -10,6 +10,7 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
+#include <linux/usb/pd.h>
 #include <linux/usb/role.h>
 #include <linux/usb/typec_mux.h>
 #include <linux/usb/typec_dp.h>
@@ -231,6 +232,43 @@ pmc_usb_mux_tbt(struct pmc_usb_port *port, struct typec_mux_state *state)
 	return pmc_usb_command(port, (void *)&req, sizeof(req));
 }
 
+static int
+pmc_usb_mux_usb4(struct pmc_usb_port *port, struct typec_mux_state *state)
+{
+	struct enter_usb_data *data = state->data;
+	struct altmode_req req = { };
+	u8 cable_speed;
+
+	req.usage = PMC_USB_ALT_MODE;
+	req.usage |= port->usb3_port << PMC_USB_MSG_USB3_PORT_SHIFT;
+	req.mode_type = PMC_USB_MODE_TYPE_TBT << PMC_USB_MODE_TYPE_SHIFT;
+
+	/* USB4 Mode */
+	req.mode_data = PMC_USB_ALTMODE_FORCE_LSR;
+
+	if (data->active_link_training)
+		req.mode_data |= PMC_USB_ALTMODE_ACTIVE_LINK;
+
+	req.mode_data |= (port->orientation - 1) << PMC_USB_ALTMODE_ORI_SHIFT;
+	req.mode_data |= (port->role - 1) << PMC_USB_ALTMODE_UFP_SHIFT;
+
+	switch ((data->eudo & EUDO_CABLE_TYPE_MASK) >> EUDO_CABLE_TYPE_SHIFT) {
+	case EUDO_CABLE_TYPE_PASSIVE:
+		break;
+	case EUDO_CABLE_TYPE_OPTICAL:
+		req.mode_data |= PMC_USB_ALTMODE_CABLE_TYPE;
+		fallthrough;
+	default:
+		req.mode_data |= PMC_USB_ALTMODE_ACTIVE_CABLE;
+		break;
+	}
+
+	cable_speed = (data->eudo & EUDO_CABLE_SPEED_MASK) >> EUDO_CABLE_SPEED_SHIFT;
+	req.mode_data |= PMC_USB_ALTMODE_CABLE_SPD(cable_speed);
+
+	return pmc_usb_command(port, (void *)&req, sizeof(req));
+}
+
 static int pmc_usb_mux_safe_state(struct pmc_usb_port *port)
 {
 	u8 msg;
@@ -272,17 +310,28 @@ pmc_usb_mux_set(struct typec_mux *mux, struct typec_mux_state *state)
 {
 	struct pmc_usb_port *port = typec_mux_get_drvdata(mux);
 
-	if (!state->alt)
-		return 0;
-
 	if (state->mode == TYPEC_STATE_SAFE)
 		return pmc_usb_mux_safe_state(port);
-
-	switch (state->alt->svid) {
-	case USB_TYPEC_TBT_SID:
-		return pmc_usb_mux_tbt(port, state);
-	case USB_TYPEC_DP_SID:
-		return pmc_usb_mux_dp(port, state);
+	if (state->mode == TYPEC_STATE_USB)
+		return pmc_usb_connect(port);
+
+	if (state->alt) {
+		switch (state->alt->svid) {
+		case USB_TYPEC_TBT_SID:
+			return pmc_usb_mux_tbt(port, state);
+		case USB_TYPEC_DP_SID:
+			return pmc_usb_mux_dp(port, state);
+		}
+	} else {
+		switch (state->mode) {
+		case TYPEC_MODE_USB2:
+			/* REVISIT: Try with usb3_port set to 0? */
+			break;
+		case TYPEC_MODE_USB3:
+			return pmc_usb_connect(port);
+		case TYPEC_MODE_USB4:
+			return pmc_usb_mux_usb4(port, state);
+		}
 	}
 
 	return -EOPNOTSUPP;